In the field of laboratory analysis, so-called cuvette tests have become standard, among others, which tests consist of cuvettes filled with a reagent, the cuvettes being placed into a laboratory analyzer for a quantitative analysis after the liquid sample has been filled in. The reagent, already filled into the cuvette by the manufacturer, reacts in a color changing manner with the analyte of the water or waste water sample to be analyzed. This color change is determined quantitatively in the laboratory analyzer by means of its photometer. For this purpose, the cuvette is photometered in the radial direction as described in DE 41 09 118 A1.